TG5 is usually reserved for low-shrinkage materials (shrinkage
: Used when standard tolerances (e.g., TG6 or TG7) are insufficient for assembly or mechanical performance but "high-precision" (TG1-TG4) costs are not justified. 3. Key Factors for Achieving TG5
Requires high-quality, professional-grade tooling. The mold must be accurate to ensure the resulting part meets the specification.
To give you a better sense of where TG5 fits, here's a comparison of common tolerance groups used in injection molding: Iso 20457 Tg5
| Parameter / Feature | Level | Recommended TG | | :--- | :--- | :--- | | | Injection Molding | 3 - 9 | | | Rotational Molding | TG 9 (or higher) | | Molding Compound Stiffness | High (Glass-filled) | Finer TG (e.g., 4 instead of 6) | | | Low (Unfilled) | Coarser TG | | Shrinkage Predictability | Exact Possible (deviation < ±10%) | Finer TG | | | Inaccurate Possible (deviation > ±20%) | Coarser TG | | Part Complexity | Simple, robust geometry | Coarser TG | | | Complex with thin walls | Finer TG | | Quality Priority | Maximum precision required | TG 4 | | | Cost-efficiency is key | TG 5 - 6 |
Elara rubbed her temples. The problem wasn’t the metal. The problem was the numbers . ISO 20457 TG5 had set an absolute threshold for internal voids—pockets of gas trapped during laser melting. If a lattice’s porosity exceeded 0.5%, the standard demanded rejection.
Implementing ISO 20457 TG5 helps prevent "fear tolerances"—unnecessarily tight requirements that add cost without improving function. It ensures that both the part designer and the manufacturer have a clear, internationally recognized agreement on what constitutes a quality part. www.makrolar.euhttps://www.makrolar.eu The mold must be accurate to ensure the
Understanding ISO 20457 TG5: Precision Tolerances in Injection Molding
ISO 20457 TG5 is a specific precision classification within the international standard ISO 20457:2018 , which defines the dimensional and geometrical tolerances for plastic molded parts. TG5 (Tolerance Group 5) is widely recognized as the baseline or standard precision grade for industrial and technical plastic applications, particularly for housings and structural components . What is ISO 20457?
ISO 20457 specifies possible manufacturing tolerances for plastic molded parts produced through processes like injection molding, extrusion, or thermoforming. It provides a framework for defining general tolerances for integral features and surface profiles within a specified datum system. The standard replaced the older German standard DIN 16742 and is now the international benchmark for plastic part tolerancing. The problem was the numbers
Precision gears, automotive connectors, and electronic housings. 3. Standard Engineering Components (TG5)
Standard precision for functional parts, balancing cost and quality.
By standardizing around , manufacturers protect themselves against the financial risks of over-tolerancing—which spikes mold tooling costs and scrap rates—while ensuring that multi-part plastic assemblies snap together flawlessly on the automated production line. 1. What is ISO 20457?
: Larger nominal dimensions require proportionally larger absolute tolerances. 2. Understanding Tolerance Group 5 (TG5)
is a highly specific geometric and dimensional tolerance classification under the international standard ISO 20457:2018 , which regulates the manufacturing limits and acceptance conditions of molded plastic parts . In plastics engineering, the Tolerance Group 5 (TG5) designation serves as the go-to standard for consumer goods, toys, and packaging. It strikes an ideal balance between technical manufacturability and cost efficiency by providing achievable dimensional and flatness boundaries ( ±0.50plus or minus 0.50